Do chemicals used to disinfect water harm our health? Evidence suggests drinking water purified with common disinfectants like chlorine and bromine causes urinary bladder cancer. But it was not clear whether the chemicals can affect health when used to keep swimming pools or bathing water clean, until now.

River banks are efficient water filters. Haridwar shows how to make most of them

by Bharat Lal Seth

The holy town of Haridwar on the banks of the Ganga has of late been receiving pilgrims of a different kind. They are students and professors from India and abroad who come to study its water supply system. Over a third (38 per cent) of the water supplied in Haridwar is naturally treated as it passes through the river banks.